A woman looks at a swimmer getting herself warm after the annual Christmas winter swimming competition in the Vltava river in Prague December 26, 2014. (Photo by David W. Cerny/Reuters)
Inbar Regev, an eight-year-old Israeli girl, holds her pet python while swimming in her backyard pool in Ge'a, southern Israel on October 7, 2020. (Photo by Amir Cohen/Reuters)
Swimmers take part in the annual Christmas Day swim in Porthcawl, Wales, England on December 25, 2019. (Photo by Ben Birchall/PA Images via Getty Images)
Team GB synchronised swimmers Kate Shortman and Izzy Thorpe took on an underwater fashion shoot in June 2021 before they represent Britain in the artistic swimming competition at the Tokyo Olympics next month. (Photo by Bluebella/Cavendish Press)
Members of the O’Neill and Gallagher families from Sydney, Australia take to the water at the 40 Foot for a Christmas Day Swim in Ireland on December 25, 2022. (Photo by Alan Betson/The Irish Times)
Karolina Kluskova of the Czech Republic formed one part of an artistic swimming duet at the European Games at Aquatics Centre in Oswiecim, Poland on June 22, 2023. (Photo by Sarah Meyssonnier/Reuters)
Divers swim beside millions of silverside fish at Devil's Grotto, Cayman Islands. Swimming in unison, millions of silverside fish dwarf the divers. The fish create waves of silver light as they move around the grottos that lie beneath the surface of the Caribbean Sea. These amazing photographs were captured by Belgian photographer Ellen Cuylaerts, 44, on a diving trip to the Devil's Grotto, Cayman Islands. (Photo by Ellen Cuylaerts/This is Guavo Media)
A swimmer stops short of a red algae bloom at Sydney's Clovelly Beach on November 27, 2012, which closed some beaches for swimming including Bondi Beach for a period of time. While the red algae, known as Noctiluca scintillans or sea sparkle, has no toxic effects, people are still advised to avoid swimming in areas with discoloured water because the algae, which can be high in ammonia, can cause skin irritation. (Photo by William West/AFP Photo)